Climate-Change Watch: Recent Findings

08-01-1999
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NWF Staff

Last year ocean temperatures reached record-high levels, leading to tropical coral bleaching, disease and death on an unprecedented scale. Coral was affected in at least 60 countries and island nations, and in some areas much of the coral died. A U.S. State Department report released in March blamed the combined effects of El Ni&ntilde;o and human-induced climate change, concluding that only global warming "could have induced such extensive bleaching simultaneously throughout the disparate reef regions of the world."

The thinning of the stratospheric ozone layer likely will be worse than previously predicted, and the culprit is the greenhouse effect, according to an analysis by New Scientist of the latest research. As greenhouse gases such as carbon dioxide, released from the burning of fossil fuels, hold warmth close to the planet&acute;s surface, the outer atmosphere is cooling 10 times faster than previously expected. The cold creates ideal conditions for the process of ozone depletion--caused
by chemicals such as freon, once widely used in refrigerators and air conditioners. New models that incorporate these phenomena, including one developed at NASA, predict that ozone holes at both poles will grow larger, and repair of the layer will be delayed.

The growing season has lengthened across Europe by an average of 11 days, concluded a recent study of plants at 77 experimental gardens in locations that range from the Mediterranean to Scandinavia. The plants, identical species of trees and shrubs, are flowering earlier and losing their leaves later than they did 30 years ago.

The 1990s have been the warmest decade of the past 1,000 years. That&acute;s the conclusion of scientists from the University of Massachusetts and the University of Arizona who gauged temperatures from the past by analyzing tree rings and samples of glacial ice.